Multi-valve injection/aspiration manifold with needleless access connection

ABSTRACT

An IV manifold includes a plurality of injection/aspiration ports including a needleless access port (NAC). A check valve included in the manifold is generally located at an upstream end of the manifold. However, the check valve may alternatively be located between injection ports. An aspiration port can be formed with a second seal disposed on the side of the valve element opposite a first seal. Two-way aspiration can be provided by a valve having a cage with or without compressible characteristics to accommodate low tolerance fittings. Alternatively, two way aspiration can be provided by the NAC having a single elongate valve element including a plug at one end. The elongate valve element has properties for resiliently and sealingly biasing the plug into an aperture of the NAC. In use the Plug is mechanically displaced by insertion of a male Luer for injection or aspiration.

This application is a divisional application of application Ser. No.10/113,087, filed on Apr. 1, 2002 now abandoned, which is acontinuation-in-part of application Ser. No. 09/154,939, filed on Sep.17, 1998 now U.S. Pat. No. 6,364,861, which is hereby incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to ports for injecting fluids into anintravenous (IV) line, and more specifically to injection manifoldsincluding multiple injection ports.

2. Discussion of the Prior Art

Patients are commonly injected with IV solutions which are initiallyprovided in a bottle or bag and dripped into the vein of the patientthrough an IV line. Typically an injection port is provided along theline and adapted to function with a syringe to permit an injectate to beadded to the IV solution. If a large quantity of injectate, or multipleinjectates, are to be added to the IV solution, multiple ports may berequired. In such a case, an injection manifold can be disposed in theIV line to provide multiple injection ports.

A check valve is also commonly included in the IV line where it isdisposed upstream from the injection manifold. It is the purpose of thecheck valve to permit fluid flow only in the direction of the patient.This ensures that the injectate flows downstream toward the patient, notupstream toward the IV reservoir.

The prior art is deficient in that it does not adequately provide forcheck valves at locations than upstream of the ports. Doing so has itsadvantages in certain applications in which the prior art falls short.

In the past, IV manifolds have been provided with an elongate andgenerally flat configuration in order to facilitate use of the multipleinjection ports. The flow channel through the manifold has also had thiselongate wide configuration, and consequently, has been susceptible tothe formation of air pockets, and to generally uneven flowcharacteristics. In the vicinity of the injection ports, the manifoldsof the past have also developed dead spaces where the injectate hastended to collect rather than mix with the IV solution. Other IVmanifolds have been provided with a round tube defining the flowchannel. Injection ports have been connected to this tube at a “T”junction. In this case, the flow channel has remained separate and theproblems with dead spaces in the ports have been significant.

Injection ports of the past have generally included only valves with asingle valve seal. These seals have not been capable of withstandinghigh pressure such as those sometimes associated with an injection intoan adjacent port. The resulting high back pressure has sometimes causedthe valve element to deform and lodge in the lumen of the port,rendering the port inoperative.

In the past, the ports associated with injection manifold have not beenprovided with characteristics permitting the aspiration of fluids fromthe flow channel. This is sometimes desirable in order to remove airfrom the manifold or withdraw a blood sample. In these cases, a separateaspiration port has been required in addition to the injection manifold.

Even the three valve seat system provided by the embodiment having anapertured valve element of the instant invention has some drawbacks forcertain applications. For example, this embodiment requires relativelyhigh pressure for both aspiration and injection.

Some injection ports have been provided with operative cages whichmechanically open the valves. In this case a syringe having a male Luerfitting is relied on to push the cage against the valve element in orderto open the valve. Due to wide tolerance variations in the plastic partsassociated with the syringes, the male Luer fittings can sometimesextend into the injection port a distance greater than that required toopen the valve. In many of these cases, damage to the injection port hasresulted.

Although the cage and valve element embodiment of the instant inventionprovides a means for permitting unimpeded aspiration, and although thecage of the instant invention provides for inserting a variety of maleLuers without damaging the port or manifold, the cage adds a separatepiece and increases the complexity of the overall device. With the cageembodiment, changes are also required in the port itself to accommodatethe cage. For example, a large portion of the second seat must beremoved in order to provide room for the cage.

SUMMARY OF THE INVENTION

These problems with the injection ports and manifolds of the prior artare overcome with the present invention which provides for a generallyU-shaped flow channel that extends axially of the manifold. Byrestricting the IV solution to this flow channel, the flowcharacteristics through the manifold are greatly enhanced. Importantly,there are no dead spots in the fluid flow through the manifold.Furthermore, the flow of fluid can be directed against the valve elementof the injection port to avoid dead spots around the valve. A checkvalve can be included in this manifold and disposed at one end of theelongate housing. An infusion/aspiration port is preferably disposedupstream of the other injection ports and downstream of the check valve.

Alternatively, the check valve may be located between an upstreaminjection/aspiration port and a downstream injection/aspiration port. Inthis way an injection/aspiration port may be advantageously locatedupstream of the check valve. As can be understood by those skilled inthe art, locating the check valve downstream of at least one of theinjection/aspiration ports enables either pulling IV fluid from the IVline into a syringe or reservoir of the port upstream of the check valvewithout pulling fluid from downstream of the check valve, or pulling ofinjectate from the at least one port into the IV line upstream of themanifold.

A preferred injection port is provided with two seals, a line seal and asurface seal, which provide for low pressure and high pressureoperation, respectively. When an injectate is being introduced into anadjacent port, the resulting high back pressure is resisted by the highpressure surface seal of the port.

In an injection port embodiment including a cage, the cage can beconfigured to be axially compressible. These compressiblecharacteristics accommodate the wide tolerance variations in the plasticparts which sometimes tend to cause a male Luer fitting to extend intothe injection port a distance greater than that necessary to open theassociated valve. By providing the cage with these compressiblecharacteristics, the tolerance variations are accommodated withoutdamaging the valve element.

Alternatively, and perhaps preferably, a needleless access connection(NAC) can be included in the manifold. The NAC has the advantage ofenabling the aspiration as well as the injection of fluids therethrough.This feature is achieved with a simple and reliable structure. Inoperation, a male Luer is inserted into a aperture of the NAC in orderto open a NAC valve and permit aspiration or injection of fluids throughthe NAC. As can be appreciated, the aspiration and injection through theNAC requires very low pressures.

In one aspect, the invention includes an injection port adapted for usewith an IV line. The port includes a housing defining a flow channel andhaving an injection lumen. First portions of the housing define a firstvalve seat, while second portions of the housing define a second valveseat. A valve element, disposed to extend transverse to the injectionlumen has properties for forming a first seal with the first valve seatat a first pressure, and a second seal with the second valve seat at asecond pressure greater than the first pressure. The first valve seat,which forms part of the second valve seat, has the shape of a continuousline, while the second valve seat has the shape of a continuous surface.

In another aspect, the invention includes a port for injecting aninjectate into a flow channel for aspirating a fluid from the flowchannel. The port includes a housing defining the flow channel andhaving a lumen disposed in fluid communication with the flow channel.First portions of the housing define a first valve seat while secondportions of the housing define a second valve seat. A valve element hasproperties for forming a first seal with the first valve seat and asecond seal with the second valve seat when the valve element is in anatural state. The valve element has properties for opening the firstseal in response to a positive pressure in the lumen to facilitate flowof an injectate into the flow channel. The valve element also hasproperties for opening the second seal in response to a negativepressure in the lumen in order to facilitate flow of the fluid from theflow channel into the lumen of the port. The first valve seat is formedon the side of the valve element opposite the flow channel. The secondvalve seat is formed on the side of valve element opposite the firstvalve seat. This embodiment may include a post with the second sealbeing formed around the post.

In an additional aspect of the invention an injection manifold includesa first body member and second body member forming a housing. Firstportions of the housing define a flow channel adapted to receive an IVsolution flowing in an IV line. Second portions of the housing define atleast one port with an injection lumen, the port having a outsidediameter. The first portions of the housing have a width greater thanthe outside diameter of the port and define the flow channel with awidth less than the diameter of the port. The flow channel willtypically have a U-shaped configuration.

In a further aspect of the invention an injection/aspiration portincludes a housing with first portions defining a flow channel andsecond portions defining an injection/aspiration lumen. Third portionsof the housing define a valve seat around the lumen. A valve element isbiased toward the injection/aspiration lumen and forms a seal with thevalve seat. A valve cage is disposed in the lumen and adapted to bemoved by insertion of a male Luer fitting into the lumen against thevalve element to open the seal and permit two-way flow between the lumenand the flow channel. The valve cage is axially compressible toaccommodate slight variations in the size of the male Luer fitting.

These and other features and advantages of the present invention will bemore apparent with a description of preferred embodiments and referenceto the associated drawings.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an arm of a patient with an IV solutionappropriately administered through an injection manifold of the presentinvention;

FIG. 2A is a perspective view of the manifold having three injectionports and syringes of various sizes connected to the ports;

FIG. 2B is a perspective view of an additional embodiment of themanifold having two injection ports and a NAC and syringes of varioussizes connected to the port and NAC;

FIG. 3A is an exploded view of the manifold of FIG. 2A illustratingfirst and second members forming a housing, and showing the interior ofthe first member and the exterior of the second member;

FIG. 3B is an exploded view of the embodiment of FIG. 2B including theNAC;

FIG. 3C is an exploded view of a further embodiment similar to FIG. 3Awith the check valve disposed between two of the ports;

FIG. 4A is an exploded view similar to FIG. 3A but showing the interiorof the second member and the exterior of the first member;

FIG. 4B is an exploded view similar to FIG. 4A of the embodiment of FIG.3B including the NAC;

FIG. 4C is an exploded view similar to FIG. 4B of the embodiment of FIG.3C;

FIG. 4D is an exploded perspective view of the embodiment of FIG. 3Cwith the check valve disposed between two ports;

FIG. 5 is a side elevation view of the manifolds illustrated in FIGS.2A-4D;

FIG. 6 is a top plan view of the manifolds illustrated in FIG. 5;

FIG. 7A is a cross-section view taken along lines 7-7 of FIG. 5;

FIG. 7B is a cross-section view taken along lines 7-7 of FIG. 5 andexplicitly incorporating the NAC and the check valve, with the checkvalve disposed between two of injection ports;

FIG. 8A is an axially cross-section view taken along lines 8-8 of FIG.6;

FIG. 8B is an axial cross-section view taken along lines 8-8 of FIG. 6and explicitly showing the NAC and the check valve, with the check valvedisposed between two of the injection ports;

FIG. 9 is a cross-section view taken along lines 9-9 of FIG. 6;

FIG. 10 is a cross-section view similar to FIG. 9 and illustrating afurther embodiment of the manifold;

FIG. 11 is a radial cross-section view of an injection port taken alonglines 11-11 of FIG. 6;

FIG. 12 is a radial cross-section view of the injection port taken alonglines 12-12 of FIG. 6;

FIG. 13 is a cross-section view illustrating the port of FIG. 12 in ahigh pressure configuration;

FIG. 14-16 are cross-section views similar to FIG. 12 illustratingoperation of an injection port which also has aspirationcharacteristics;

FIG. 14 is a cross-section view similar to FIG. 12 and showing a furtherembodiment of the invention with a valve in a normal state;

FIG. 15 is a cross-section view similar to FIG. 14 and illustrating thevalve in an injection state;

FIG. 16 is a cross-section view similar to FIG. 14 and illustrating thevalve in an aspiration state;

FIGS. 17 and 18 are cross-section views similar to FIG. 12 andillustrating a further embodiment including a mechanical cage foractuating the valve element;

FIG. 17 is a cross-section view similar to FIG. 12 and showing the valvein a normal sealed state;

FIG. 18 is a cross-section view similar to FIG. 17 and illustrating thecage in a compressed configuration with the valve in aninjection/aspiration state; and

FIG. 19 is a section view of an end of the manifold of the second andthird alternative embodiment similar to FIG. 8B.

DESCRIPTION OF THE PREFERRED EMBODIMENTS AND BEST MODE OF THE INVENTION

The arm and hand of a patient are illustrated in FIG. 1 and designatedgenerally by the reference numeral 10. An IV solution 12 contained in areservoir, such as a bottle or bag 14, is appropriately communicated tothe patient 10 through an IV line 16. An injection manifold 18 of thepresent invention is connected in series with the line 16 and provides asite where drugs and other fluids can be injected, typically through asyringe 21, into the IV solution in the line 16.

The manifold 18 of a preferred embodiment is illustrated in greaterdetail in FIG. 2. In this view it can be seen that the manifold 18 has ahousing 23 with an elongate configuration, and extends generally alongan axis 25. The housing 23 is connected in series with the IV line 16,for example by a pair of connectors 22 and 24, so that the flow channeland the IV line 16 also extends through the housing 23.

A plurality of injection ports 27, 30 and 32 can be molded integrallywith the housing 23 and spaced along the length of the housing 23. InFIG. 2, a 60 mm syringe 34 is connected to the port 32, while a 10 mmsyringe 36 and a 5 mm syringe 38 are connected to the ports 30 and 27,respectively. There will of course be situations requiring threesyringes such as the 60 cc syringe 34 that must be coupled to themanifold 18 at the same time. This will require that the ports 27, 30and 32 be spaced sufficiently that the ports 27 and 32 are separated bya distance equal to two times the diameter of the 60 cc syringe 34, andthe center port 30 disposed intermediate with the outer ports 27 and 32.

The manifold 18 is further illustrated in the exploded views of FIGS. 3and 4. In these views, the housing of a preferred embodiment isillustrated to include a first housing member 41 and a second housingmember 43. The first housing member 41 has in inner side 45 illustratedin FIG. 3 and an outer side 47 illustrated in FIG. 4. Similarly, thesecond housing member 43 has an inner side 46 and an outer side 48. Fromthese views it can be seen that each of ports 27, 30 and 32 includes acylinder 50, 52 and 54, respectively, which projects from the outersurface 47 of the first housing member 41. These cylinders 50, 52 and 54in turn define lumen 56, 58 and 61, respectively, which are in fluidcommunication with the flow channel 49. The cylinders 50, 52 and 54 alsoform with the first housing member 41 a plurality of cavities 63, 65 and67, respectively, which are adapted to receive associated valve elements70, 72 and 74. The operation of these ports 27, 30 and 32 will bediscussed in greater detail below.

In this particular embodiment, a check valve 76 is provided at one endof the manifold 18. In this case, the check valve 76 is formed with aplurality of pins 78 which extend from the inner side 45 in a generallycircular configuration. These pins 78 are adapted to receive a valveelement 81. The manifold 18 is intended to be connected in the IV line16 and oriented with the check valve 76 connected to the upstream sideof the line 16.

Perhaps best illustrated in FIG. 4 are a plurality of protrusions 83, 85and 87 which interrupt the flow channel 49 at each of the associatedports 27, 30 and 32, respectively. These protrusions 83, 85 and 87,which are also illustrated in the assembled view of FIG. 7 and thecross-section view of FIG. 8, are of particular advantage to the presentinvention as they disrupt the flow of the IV solution 12 along thechannel 49 and direct that flow into the associated cavities 63. Withthis directed fluid flow, the cavities 63, 65 and 67, and particularlythe valve elements 70, 72 and 74, are constantly washed so that thereare substantially no dead spots associated with the injection ports 27,30 and 32. In the past, these dead spots have been particularly commonin the concave area beneath the valve 70, 72 and 74. With the fluid flowdirected specifically onto the concave side of each element 70, 72 and74, the dead spots are greatly minimized. This diverted flow isillustrated in greater detail in FIG. 11 where the cavity 63 and valveelement 70 of the injection port 27 are washed by the IV solution flowwhich is illustrated by arrows 89.

In relation to this washing effect, FIGS. 7A-B illustrate how the valvecavities associated with ports 27, 30 and 32 have a height less thaneach of a width and a length. In this way, a flow path is formed suchthat a liquid passing through the manifold, readily impinges on anunderside of the valve elements in the cavities. Thus the structuralrelationship of height to width and length reduces stagnation. Flow isfurther enhanced by structural details in the cavities. Specifically,the portion of the cavities forming valve the valve seats and the valveelements 70, 72, 74 themselves form a concave surface on a side of thevalve elements 70, 72, 74 opposite to the valve seats.

With reference to FIG. 9, it can be seen that a preferred embodiment ofthe manifold 18 provides a flow channel 49 with a U-shapedconfiguration. This shape is generated by providing the inner surface 45of the first housing member 41 with a generally planar configuration.When the second housing member 43 is mated to the first housing member41, a U-shaped cavity 90 in the surface 48 automatically provides theflow channel 49 with the U-shape desired. In this particular embodiment,the generally planar inner surface of the housing member 41 makes itpossible to also provide the outer surface 47 with a planarconfiguration. This shape greatly facilitates wiping the manifold 18between the adjacent ports 27 and 30, and the ports 30 and 32.

In an alternative embodiment illustrated in FIG. 10, the flow channel 49is defined by the U-shaped cavity 90 formed in the first housing member41, and by a second U-shaped cavity 92 formed in the second housingmember 43. When these parts are joined, the two cavities 90 and 92provide the flow channel 49 with the shape of an oval. The viewspresented by FIGS. 9 and 10 also are best suited to illustrate themating relationship of the first housing member 41 and the secondhousing member 43. These members 41 and 43 are operatively positionedwith their respective surfaces 45 and 46 in close proximity so thatthese surfaces do not form any part of the flow channel 49. Thiscontributes greatly to the flow characteristics within the channel 49and avoids many of the air pockets and dead spots associated with thefull-width flow channels of the prior art. The second housing member 43can be fixed to the first housing member 41 in this operative positionby means of adhesive or by heat seals 94.

Operation of the injection port 27 is best described with reference toFIGS. 12 and 13. In these views, it will be noted that the port 27includes portions 96 which define a first valve seat and portions 98which define a second valve seat. The first valve seat 96 forms a slightannulus above the valve element 70. In its normal configuration, thevalve element 70, which has elastomeric properties, is biased by theprotrusion 83 beneath the element 70 to form a seal with the first valveseat 96.

When an injectate is introduced through one of the adjacent ports, suchas port 30 or 32, a relatively high pressure occurs in the flow channel49. By operation of the check valve 76, this pressure is exerted againstthe underside of the valve element 70 of the port 27. In the manifold18, the higher pressure will cause the valve element 70 to deform asillustrated in FIG. 13 until it comes into contact with the second valveseat 98 as illustrated in FIG. 13. With this second valve seat 98providing surface contact with the valve element 70, a high pressureseal is formed without radical deformation or damage to the valveelement 70.

Under some circumstances, it is desirable to have an injection port,such as the port 32, function not only to receive injectate into theflow channel 49, but also to aspirate or withdraw fluid from the flowchannel 49. When an injection/aspiration port, such as the port 32, isincluded in the manifold 18, it is preferably disposed on the upstreamside of the other ports so that injectate introduced in the other portsis not aspirated from the manifold 18. Since the check valve 76 is alsoto be positioned upstream of the ports 27-32, it is desirable that theinjection/aspiration port 32 be positioned next to the check valve 76.

A preferred configuration for the injection/aspiration port 32 isillustrated in FIGS. 14-16. In this embodiment, the projection 87 isconfigured with a shoulder 101 which forms a third valve seat 103, and apost extending toward the lumen 61 of the port 32. In this case, thevalve element 74 is provided with a central aperture or hole 107 whichis sized to receive the post 105. In the manner previously discussedwith reference to the FIG. 12 embodiment, a first valve seat 110 can beformed above the valve elements 74 with the third valve seat 103 formedbeneath the valve element 74. In its normal state, the port 32 ispositioned with the valve element 74 biased to form a first seal withthe first valve seat 110 and a second seal with a third valve seat 103as illustrated in FIG. 14. Under the fluid pressure of an injectate, asillustrated by an arrow 112 in FIG. 15, the valve element 74 is bentdownwardly opening the first seal at the first valve seat 110. Thesecond seal with the valve seat 103 is strengthened by this downwardpressure against the valve element 74. Nevertheless, the injectate 112flows through the first valve and into the flow channel 49.

Aspiration is accommodated by applying a suction to the lumen 61 asillustrated by an arrow 114 in FIG. 16. This causes the valve element 74to raise off of the shoulder 103 which form the second valve seat. Fluidwithin the flow channel 49 is thereby permitted to pass between thevalve element 74 and the post 105 into the lumen 61. In all cases, thehole 107 in the valve element 74, and the post 105, maintain the valveelement 74 centered with respect to the valve seats 110 and 103,respectively.

A further embodiment of the injection/aspiration port 32 is illustratedin FIGS. 17 and 18. In this case, the port 32 is operated not by fluidpressure, but rather mechanically by the force of the syringe 38 actingupon a cage 121. In this case, the cylinder 54 defining the lumen 61 isprovided with an interior shoulder which faces downwardly and preventsthe cage 121 from moving upwardly within the lumen 61. In thisembodiment, the cage 121 fits between the shoulder 123 of the cylinder54 and the upper surface of the valve element 74. The cage 121 can beformed of wire or other resilient material and provided with aconfiguration which is axially compressible. The advantage of this port32 is that it does not rely upon fluid pressure to open, but rather themechanical force of a male Luer fitting 123 associated with the syringe38.

With the tolerances accommodated in forming the Luer fitting 123 and informing the lumen 61, it can be appreciated that the syringe 38 canextend a variable distance into the cylinder 54. If the cage 121 isprovided only as a rigid element, damage to the valve element 74 canresult when the male Luer fitting 123 extends too far into the lumen 61.In the illustrated embodiment, wherein the cage 121 is axiallycompressible, this great variation in distance of insertion can beaccommodated by the cage 121 so that the valve element 74 is notradically deformed. When the valve element 74 is opened by the cage 121,two-way flow through the port 32 can be accommodated as illustrated bythe arrows 125 in FIG. 18. Thus, the valve element 74 is separated fromthe valve seat 110 opening the valve to either receive injectate intothe flow channel 49 or remove fluid from the flow channel 49.

FIG. 2B illustrates a modified manifold 130. The modified manifold 130differs from the embodiment of FIG. 2A in that a port 27 has beenreplaced by a needleless access connection (NAC) 132. All other aspectsof the manifold remain the same. However, the NAC has several detailsthat are unique and important. The NAC is made up of a body portion 133having a top piece 134 thereon. The top piece has an aperture 135therethrough forming part of a conduit through the NAC body 133. The toppiece 134 is also provided with a fastening means 136. A bottom end 137of the NAC 132 is connected to the housing 23. In this embodiment, theNAC can be rigidly connected to or formed integrally with the housing23.

FIG. 3B perhaps best illustrates an aspect of the NAC bottom end 137.This aspect is a grate 138 integrally formed with the bottom end 137.Grate 138 provides an opening 141 through which fluid may flow. At thesame time, grate 138 retains an elongate valve element 143 within theNAC 132. The elongate valve element is further retained by a shoulder144 formed on the interior of top piece 134. In this way, the elongatevalve element 143 is captured in the NAC 132 and extends between thegrate 138 and the top piece 134.

As can be seen from FIG. 4C, the grate 138 may be replaced by a gratemeans 145. In this embodiment the grate means 145 is not formedintegrally with the NAC body portion 133. Rather the grate means 145 isformed separately as a part of housing member 43. In this way, it can beappreciated that the elongate valve element 143 will be captured in theNAC 132 when the housing members 41 and 43 are assembled together.Importantly, grate means 145 still provides an opening at a bottom endof the NAC 132. This opening is provided by slot 147 and other structurethat permits fluid to flow in and out of a bottom end 137 of NAC 132.

As can be seen in the Figures, the NAC has a diameter of width greaterthan the other injection valves, yet narrower than the housing of themanifold 132. The bottom end 137 of the NAC 132 is rigidly connected tothe manifold housing. Furthermore, the bottom end 137 of the NAC 132 hasan opening for placing the conduit or interior of the NAC 132 in fluidcommunication with the flow channel 49 of the manifold 132

A second alternative embodiment or modified manifold 152 is perhaps bestillustrated in FIG. 3C. The second modified manifold 152 is differentfrom the manifold 18 in that the locations of the injection port 32 andthe check valve 76 have been interchanged. All other aspects remainsubstantially the same. However, additional flow channel 154 bestillustrated in FIG. 4A and FIG. 19 have a different and significantrelationship to other elements of the invention in this embodiment. Theadditional flow channel 154 of the previously described embodimentsnormally defines a flow between an IV fluid inlet and a first port 32.However, in the second modified manifold 152 the additional flow channel154 now defines a flow path for the IV fluid between the injection port32 and flow channel 49. In this case additional flow channel 154 is indirect fluid communication with flow channel 49.

FIG. 19 illustrates how the second modified manifold advantageouslyfunctions. As shown, injection flow through port 32 and indicated byarrows 156 can be caused by a net negative pressure in the upstreamportion of the IV line. Of course, if the net negative pressure is in adownstream portion of the IV line relative to the check valve 76, thenflow 156 will move through the check valve 76 and downstream. However,as can be appreciated, by manipulating the pressure upstream of themanifold in the IV line between a negative net pressure and a positivenet pressure, the flow may be alternated between an injection flow 156and a downstream through flow 158. By thus cycling negative and positivepressures upstream in the IV line, a repeated draw of fluid from areservoir connected to port 32 and a forcing through of the fluidthrough the manifold may be achieved. Of course, a single cycle or ahalf cycle may be implemented as well.

A third alternative embodiment or alternatively modified manifold 165 isdepicted in FIG. 5. As shown in dashed lines the manifold of thisembodiment incorporates the NAC 132 in place of port 27 and interchangedlocations of injection port 32 and the check valve 76. All other aspectsof the manifold are substantially the same.

FIG. 7B is a sectional view along lines 7-7 of FIG. 5 and explicitlyshowing the third alternatively modified manifold 165. Likewise, FIG. 8Bis a sectional view taken along lines 8-8 of FIG. 6 and also shows thethird alternatively modified manifold 165.

FIG. 8B best illustrates the elongate valve element 143 of the first andthird alternative embodiments. The elongate valve element 143 has a plug170 at its upper end and an elastomeric shaft 172 extending downwardlyand engaging the grate 138. As can be appreciated, the elastomeric shaftresiliently biases the plug 170 into the aperture 135 of the NAC 132.

In use, when a male Luer is forced into the aperture 135 of the NAC andseals the NAC against fluid passage or reflux in and out of the top ofthe NAC. The plug 170 is resiliently displaced downwardly into the NAC132. The elastomeric shaft 172 cants and permits this displacement, andfluid communication is thereby established between the Luer tip and theNAC. The elastomeric shaft 172 may include structural features thatenhance canting such as, for example, recesses in the elastomeric shaft172. It can also be appreciated that the height of the NAC and theresiliency of the elongate valve element 143 accommodate a wide range ofmale Luer lengths without harming or adversely affecting the manifold.

The NAC of the instant invention has an advantage over many of theinjection ports described above in that the NAC may be used foraspiration as well as for injection of fluids therethrough. Furthermore,the NAC is capable of operating at lower pressures. For example, the NACmay be operated at pressures of 1.5 psi or less depending on otherrelative pressures in the system. On the other hand the injection portsof the previously described embodiments operate at higher pressures.That is, for example, in the range of 2-6 psi. As can be appreciated bythose skilled in the art the NAC therefore can be appropriately used toinject fluids therethrough from an IV bottle or bag source.

It will be appreciated that many variations of these embodiments willnow be apparent to those skilled in the art. Certainly, theconfiguration of the flow channel 49 can be varied widely to accommodateand improve fluid flow through the manifold 18. Also, the shape of theprojections 83, 85 and 87 can be varied considerably as long as thefluid flow is directed into the cavities containing the valve elements.Other embodiments providing multiple valve seats to accommodate high andlow pressures will also be apparent. In addition, other portsfacilitating aspiration from the flow channel 49 will also be apparentto either provide two-way fluid communication or alternatively tootherwise direct the fluid flow as illustrated in the Figures.

Based on these and many other variation which will now be apparent, oneis cautioned not to determine the extent of the concept only withreference to the disclosed and illustrated embodiments, but rather todetermine the scope of the invention only with reference to thefollowing claims.

1. An injection port adapted for use with an intravenous line,comprising: a housing defining a flow channel and having an injectionlumen extending in fluid communication with the flow channel; firstportions of the housing defining a first valve seat around the injectionlumen; second portions of the housing defining a second valve seataround the injection lumen; a valve element disposed to extendtransverse to the injection lumen; the valve element forming a firstseal with the first valve seat in response to a first pressure, thefirst pressure resulting from fluid in the flow channel; the valveelement forming a second seal with the second valve seat in response toa second pressure, the second pressure resulting from fluid in the flowchannel, the second pressure greater than the first pressure of thefluid in the flow channel, and the valve element forming an openconfiguration between said lumen and said flow channel in response to athird pressure resulting from fluid in the injection lumen the thirdpressure greater than one of said first pressure and said secondpressure.
 2. The injection port recited in claim 1, further comprising:third portions of the housing defining a third valve seat on the side ofthe valve element opposite the first and second valve seats; and thevalve element having properties for forming a third seal with the thirdvalve seat.
 3. The injection port recited in claim 2, wherein the valveelement has properties for opening at least the first seal for said openconfiguration under the pressure of an injectate in the injection lumento create a flow path around the valve element between the injectionlumen and the flow channel; and the valve element has properties foropening the third seal in response to a partial vacuum in the injectionlumen to aspirate a portion of the fluid in the flow channel through anaperture in the valve element and into the injection lumen.